PowerShell script to look for particular word in the file and add “4” at the beginning of the line - linux

Question

I am the best. Page
I am good. Page
I am funny. Page
Output:
4 I am the best. Page
4 I am good. Page
4 I am funny. Page
PowerShell script needs to look for “page” and add “4” at the beginning of the line. I have created this script:
powershell -Command “sed ‘s/^Page/4 &/‘c:\users*.txt >test.txt”
but it didn't work in PowerShell.

Answer 1

This ought to do it:
$content = Get-Content "C:\path\to\my\file.txt"
$newcontent = $null
Foreach($line in $content)
{
if($line -ne "")
{
$line = "4 "+"$line`r`n"
$newcontent += $line
}
else
{
$newcontent += "`r`n"
}
}
Set-Content -Path "C:\path\to\my\file.txt" -Value $newcontent

Answer 2

powershell -command "foreach($ln in cat 'c:\users*.txt'){if($ln -match 'page'){write-host '4'$ln}}"
or
powershell -command "foreach($ln in cat 'c:\users*.txt'){if($ln -match 'page'){write-host '4'$ln}else{echo $ln}}"
depending on whether you only want to output lines with "page" in them.
Note also that powershell does not have a built in alias for sed and your /^Page/ would have only matched "page" at the beginning of a line in anycase.

Answer 3

sed is a Unix commandline tool that isn't commonly installed on Windows (although there are Windows ports of it).
The PowerShell way of doing what you're asking is
(Get-Content 'c:\users\*.txt') -replace '.*page','4$&' | Set-Content 'test.txt'
or (using aliases and redirection for reduced typing):
(cat 'c:\users\*.txt') -replace '.*page','4$&' > 'test.txt'
If you want to update each file separately (note: that is NOT what your Unix code snippet does) you'd do something like this:
Get-ChildItem 'C:\users\*.txt' | ForEach-Object {
(Get-Content $_.FullName) -replace '.*page','4$&' | Set-Content $_.FullName
}
or (again using aliases):
ls 'c:\users\*.txt' | %{(cat $_.FullName) -replace '.*page','4$&' | sc $_.FullName}
Note that you cannot use redirection in this case, because the redirection operator would open the file for writing before cat could read it, which would effectively truncate the file.